An enormous, yellowish-tinged patch of moisture that appears on a surface that has been lived-on by a large, smelly creature for a long period of time. The most common place for this to appear is on the bed of the being in question, or possible the rim of a toilet seat. The moisture usually consists of a build up of smelly odours given off by the creature.

'Bloody hell, did you see that danpatch on Mills' bed? He seriously needs to stop sweating so much.'